Gemini 3.5 Flash Lite vs GPT-6 Astra
GPT-6 Astra leads Gemini 3.5 Flash Lite on coding, 85.1 to 49.0 on the Vibe Coding Index, and Gemini 3.5 Flash Lite costs 20.0x less per output token ($2.50 vs $50.00 per million). Updated October 22, 2026; 74 benchmarks have a result for both.
Gemini 3.5 Flash Lite or GPT-6 Astra: which to pick
Pick GPT-6 Astra for coding: it scores 85.1 on the Vibe Coding Index against 49.0 for Gemini 3.5 Flash Lite.
Pick Gemini 3.5 Flash Lite for output tokens 20.0x cheaper ($2.50 vs $50.00 per million) and work measured by CyberBench (Vals AI) or LMArena Text: medicine and healthcare, where it leads.
- Shared results
- 74
- Gemini 3.5 Flash Lite only
- 11
- GPT-6 Astra only
- 47
- Like-for-like categories
- 7 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, six public coding benchmarks
GPT-6 Astra
GPT-6 Astra scores 85.1 against 49.0.
3 and 5 benchmarks behind the scores
Intelligence
AA Intelligence Index
GPT-6 Astra
GPT-6 Astra leads, 52.7 against 22.2.
Same board, both measured
Agentic work
AA Agentic Index
GPT-6 Astra
GPT-6 Astra leads, 51.0 against 14.3.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only Gemini 3.5 Flash Lite has a GPQA Diamond result, 83.8%.
Directional only
Knowledge
MMLU Pro
No call
Only Gemini 3.5 Flash Lite has a MMLU Pro result, 85.8%.
Directional only
Web design
Design Arena: websites
No call
Only GPT-6 Astra has a Design Arena: websites result, 1336.
Directional only
General
Vals Index
No call
Only GPT-6 Astra has a Vals Index result, 65.0%.
Directional only
Long documents
Listed context window
GPT-6 Astra
GPT-6 Astra takes 1.05M tokens against 1.05M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite $0.0015, GPT-6 Astra $0.035 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Gemini 3.5 Flash Lite has the number, $0.41.
Directional only
At a glance
- Coding index
- Gemini 3.5 Flash Lite 49.0 from 3 benchmarks, GPT-6 Astra 85.1 from 5 benchmarks.
- Widest category
- Math, 49.0 points apart on average over 6 shared benchmarks.
- Widest single gap
- FrontierMath, tier 4: Gemini 3.5 Flash Lite 0.0% against GPT-6 Astra 97.6%, 97.6 points apart on a 0 to 100 scale.
- Output price
- Gemini 3.5 Flash Lite $2.50 against GPT-6 Astra $50.00 per million output tokens, 20.0x apart.
- Context window
- Gemini 3.5 Flash Lite takes 1.05M tokens, GPT-6 Astra 1.05M.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | Gemini 3.5 Flash Lite | Bars | GPT-6 Astra | Ties |
|---|---|---|---|---|
| Coding | 1 | 14 | ||
| Intelligence | 0 | 2 | ||
| Agentic work | 0 | 6 | ||
| Reasoning | 0 | 12 | ||
| Math | 0 | 6 | ||
| Knowledge | 1 | 5 | ||
| General | 7 | 20 | ||
| All shared boards | 9 | 65 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index114
| Benchmark | Gemini 3.5 Flash Lite | GPT-6 Astra | Leader |
|---|---|---|---|
| LiveBench coding | Not measured | 93.7% | Only GPT-6 Astra measured |
| LMArena WebDev | 1435 | 1774 | GPT-6 Astra |
| AA Coding Index | 49.3 | 76.9 | GPT-6 Astra |
| LiveCodeBench (Vals AI) | 79.0% | Not measured | Only Gemini 3.5 Flash Lite measured |
| SWE-bench Verified (Vals AI) | 75.0% | Not measured | Only Gemini 3.5 Flash Lite measured |
| Terminal-Bench 4 (Vals AI) | Not measured | 59.6% | Only GPT-6 Astra measured |
| Vibe Code Bench (Vals AI) | 37.2% | 89.6% | GPT-6 Astra |
| Code migration (Vals AI) | 6.2% | 67.7% | GPT-6 Astra |
| ProgramBench (Vals AI) | 0.0% | 5.5% | GPT-6 Astra |
| IOI (Vals AI) | Not measured | 100.0% | Only GPT-6 Astra measured |
| Terminal-Bench 2.1 (Vals AI) | 50.2% | 87.3% | GPT-6 Astra |
| SWE-bench Multimodal (Vals AI) | Not measured | 43.3% | Only GPT-6 Astra measured |
| Vibe Code Bench 1-100 (Vals AI) | Not measured | 27.6% | Only GPT-6 Astra measured |
| CyberBench (Vals AI) | 59.1% | 41.1% | Gemini 3.5 Flash Lite |
| SciCode | 41.3% | 56.5% | GPT-6 Astra |
| FrontierCode | Not measured | 53.3% | Only GPT-6 Astra measured |
| FrontierSWE | Not measured | 65.5% | Only GPT-6 Astra measured |
| GSO-Bench | Not measured | 79.4% | Only GPT-6 Astra measured |
| WeirdML | 39.0% | 93.3% | GPT-6 Astra |
| MirrorCode | Not measured | 46.7% | Only GPT-6 Astra measured |
| ALE-Bench | 765.3 | 2951.3 | GPT-6 Astra |
| LMArena Text: coding | 1453 | 1489 | GPT-6 Astra |
| LMArena Text: software and IT | 1451 | 1474 | GPT-6 Astra |
| LMArena WebDev: React | 1408 | 1798 | GPT-6 Astra |
| LMArena WebDev: HTML | Not measured | 1775 | Only GPT-6 Astra measured |
| LMArena WebDev: from an image | 1448 | 1726 | GPT-6 Astra |
| SciCode | 6.2% | 12.3% | GPT-6 Astra |
| Neither model has a result on the other 12 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Gemini 3.5 Flash Lite | GPT-6 Astra | Leader |
|---|---|---|---|
| AA Intelligence Index | 22.2 | 52.7 | GPT-6 Astra |
| Epoch Capabilities Index | 144.9 | 168.8 | GPT-6 Astra |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index06
| Benchmark | Gemini 3.5 Flash Lite | GPT-6 Astra | Leader |
|---|---|---|---|
| AA Agentic Index | 14.3 | 51.0 | GPT-6 Astra |
| Design Arena: agents building web apps | Not measured | 1373 | Only GPT-6 Astra measured |
| Design Arena: agents building full-stack apps | Not measured | 1357 | Only GPT-6 Astra measured |
| Design Arena: agents building mobile apps | Not measured | 1312 | Only GPT-6 Astra measured |
| Design Arena: agents building Godot games | Not measured | 1348 | Only GPT-6 Astra measured |
| Design Arena: PowerPoint slides | Not measured | 1219 | Only GPT-6 Astra measured |
| Design Arena: spreadsheets | Not measured | 1365 | Only GPT-6 Astra measured |
| LiveBench research | Not measured | 85.2% | Only GPT-6 Astra measured |
| LiveBench browser | Not measured | 84.0% | Only GPT-6 Astra measured |
| LiveBench long agentic | Not measured | 82.4% | Only GPT-6 Astra measured |
| SREBench (Vals AI) | Not measured | 56.9% | Only GPT-6 Astra measured |
| Finance Agent (Vals AI) | 47.4% | 53.5% | GPT-6 Astra |
| Tax Agent Bench (Vals AI) | 7.2% | 20.7% | GPT-6 Astra |
| Legal Research Bench (Vals AI) | 13.9% | 39.4% | GPT-6 Astra |
| Harvey's Legal Agent Benchmark (Vals AI) | Not measured | 7.1% | Only GPT-6 Astra measured |
| Excel Modeling Benchmark (Vals AI) | 43.2% | 71.7% | GPT-6 Astra |
| BioMysteryBench (Vals AI) | Not measured | 79.3% | Only GPT-6 Astra measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 62.9% | Only GPT-6 Astra measured |
| Vals Science Index | Not measured | 65.1% | Only GPT-6 Astra measured |
| Time Horizon Index (Vals AI) | Not measured | 90.5% | Only GPT-6 Astra measured |
| CUA-bench (Vals AI) | Not measured | 19.2% | Only GPT-6 Astra measured |
| Robo-bench (Vals AI) | Not measured | 23.3% | Only GPT-6 Astra measured |
| APEX-Agents | 29.3% | 64.7% | GPT-6 Astra |
| Remote Labor Index | Not measured | 20.8% | Only GPT-6 Astra measured |
| BALROG | Not measured | 68.3% | Only GPT-6 Astra measured |
| SpireClimb | Not measured | 25.7% | Only GPT-6 Astra measured |
| Vending-Bench 2 | Not measured | $15,515 | Only GPT-6 Astra measured |
| Neither model has a result on the other 14 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index012
| Benchmark | Gemini 3.5 Flash Lite | GPT-6 Astra | Leader |
|---|---|---|---|
| GPQA Diamond | 83.8% | Not measured | Only Gemini 3.5 Flash Lite measured |
| LiveBench reasoning | Not measured | 92.7% | Only GPT-6 Astra measured |
| MysteryMechanism (Vals AI) | Not measured | 53.1% | Only GPT-6 Astra measured |
| MMMU Pro (Vals AI) | 83.6% | Not measured | Only Gemini 3.5 Flash Lite measured |
| GPQA Diamond (Artificial Analysis run) | 83.8% | 96.3% | GPT-6 Astra |
| Humanity's Last Exam (Artificial Analysis run) | 18.8% | 54.7% | GPT-6 Astra |
| GPQA Diamond (Epoch AI run) | 83.3% | 95.8% | GPT-6 Astra |
| ARC-AGI | 53.5% | 98.5% | GPT-6 Astra |
| ARC-AGI-2 | 10.3% | 95.0% | GPT-6 Astra |
| Chess puzzles | 21.0% | 74.0% | GPT-6 Astra |
| Mystery game puzzles | 19.0% | 84.0% | GPT-6 Astra |
| EBR-bench | Not measured | 76.2% | Only GPT-6 Astra measured |
| LMArena Text: hard prompts | 1441 | 1463 | GPT-6 Astra |
| LMArena Text: expert | 1434 | 1489 | GPT-6 Astra |
| LMArena Text: hard prompts in English | 1440 | 1464 | GPT-6 Astra |
| LMArena Vision: diagrams | 1284 | 1297 | GPT-6 Astra |
| LMArena Vision: homework | 1291 | 1337 | GPT-6 Astra |
| Neither model has a result on the other 5 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index06
| Benchmark | Gemini 3.5 Flash Lite | GPT-6 Astra | Leader |
|---|---|---|---|
| OTIS Mock AIME | 71.1% | 100.0% | GPT-6 Astra |
| FrontierMath, tiers 1 to 3 | 26.0% | 93.7% | GPT-6 Astra |
| FrontierMath, tier 4 | 0.0% | 97.6% | GPT-6 Astra |
| ProofBench | 13.0% | 99.0% | GPT-6 Astra |
| LMArena Text: math | 1434 | 1465 | GPT-6 Astra |
| LMArena Text: mathematical work | 1433 | 1484 | GPT-6 Astra |
| Neither model has a result on the other 7 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index15
| Benchmark | Gemini 3.5 Flash Lite | GPT-6 Astra | Leader |
|---|---|---|---|
| MMLU Pro | 85.8% | Not measured | Only Gemini 3.5 Flash Lite measured |
| LegalBench (Vals AI) | 84.1% | Not measured | Only Gemini 3.5 Flash Lite measured |
| CorpFin (Vals AI) | 60.7% | Not measured | Only Gemini 3.5 Flash Lite measured |
| TaxEval (Vals AI) | 72.6% | Not measured | Only Gemini 3.5 Flash Lite measured |
| MortgageTax (Vals AI) | 68.7% | Not measured | Only Gemini 3.5 Flash Lite measured |
| MedCode (Vals AI) | 43.5% | 48.5% | GPT-6 Astra |
| SimpleQA Verified | Not measured | 75.6% | Only GPT-6 Astra measured |
| LMArena Text: science | 1451 | 1451 | GPT-6 Astra |
| LMArena Text: medicine and healthcare | 1438 | 1425 | Gemini 3.5 Flash Lite |
| LMArena Text: legal and government | 1431 | 1462 | GPT-6 Astra |
| LMArena Text: business and finance | 1423 | 1439 | GPT-6 Astra |
| FACTS Benchmark Suite | 53.5% | 75.7% | GPT-6 Astra |
| Neither model has a result on the other 6 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index9 boards, none shared
| Benchmark | Gemini 3.5 Flash Lite | GPT-6 Astra | Leader |
|---|---|---|---|
| Design Arena: websites | Not measured | 1336 | Only GPT-6 Astra measured |
| Design Arena: UI components | Not measured | 1393 | Only GPT-6 Astra measured |
| Design Arena: game dev | Not measured | 1478 | Only GPT-6 Astra measured |
| Design Arena: data viz | Not measured | 1335 | Only GPT-6 Astra measured |
| Design Arena: 3D | Not measured | 1500 | Only GPT-6 Astra measured |
| Design Arena: all code categories | Not measured | 1379 | Only GPT-6 Astra measured |
| Design Arena: SVG | Not measured | 1431 | Only GPT-6 Astra measured |
| Design Arena: ASCII art | Not measured | 1353 | Only GPT-6 Astra measured |
| LiveBench design | Not measured | 82.0% | Only GPT-6 Astra measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index720
| Benchmark | Gemini 3.5 Flash Lite | GPT-6 Astra | Leader |
|---|---|---|---|
| Vals Index | Not measured | 65.0% | Only GPT-6 Astra measured |
| LiveBench data analysis | Not measured | 83.0% | Only GPT-6 Astra measured |
| Public Benefits Bench (Vals AI) | 51.8% | Not measured | Only Gemini 3.5 Flash Lite measured |
| SAGE (Vals AI) | 47.3% | 46.4% | Gemini 3.5 Flash Lite |
| MedScribe (Vals AI) | 70.9% | 87.9% | GPT-6 Astra |
| Long context reasoning (AA-LCR) | 76.0% | 80.7% | GPT-6 Astra |
| DTBench | 83.5% | 97.3% | GPT-6 Astra |
| LMCA | 37.6% | 64.4% | GPT-6 Astra |
| Furniture assembly | Not measured | 80.0% | Only GPT-6 Astra measured |
| LMArena Text | 1435 | 1441 | GPT-6 Astra |
| LMArena Text: instruction following | 1419 | 1455 | GPT-6 Astra |
| LMArena Text: creative writing | 1421 | 1420 | Gemini 3.5 Flash Lite |
| LMArena Vision | 1269 | 1280 | GPT-6 Astra |
| LMArena Text: English | 1438 | 1447 | GPT-6 Astra |
| LMArena Text: non-English | 1427 | 1432 | GPT-6 Astra |
| LMArena Text: Chinese | 1468 | 1489 | GPT-6 Astra |
| LMArena Text: German | 1454 | 1459 | GPT-6 Astra |
| LMArena Text: Japanese | 1426 | 1405 | Gemini 3.5 Flash Lite |
| LMArena Text: Korean | 1407 | 1428 | GPT-6 Astra |
| LMArena Text: French | 1451 | 1432 | Gemini 3.5 Flash Lite |
| LMArena Text: Spanish | 1441 | 1422 | Gemini 3.5 Flash Lite |
| LMArena Text: Russian | 1443 | 1438 | Gemini 3.5 Flash Lite |
| LMArena Text: Polish | 1437 | 1422 | Gemini 3.5 Flash Lite |
| LMArena Text: multi-turn | 1445 | 1447 | GPT-6 Astra |
| LMArena Text: longer queries | 1435 | 1460 | GPT-6 Astra |
| LMArena Text: writing and language | 1428 | 1437 | GPT-6 Astra |
| LMArena Text: entertainment and media | 1414 | 1427 | GPT-6 Astra |
| LMArena Vision: English | 1269 | 1280 | GPT-6 Astra |
| LMArena Vision: Chinese | 1311 | 1361 | GPT-6 Astra |
| LMArena Vision: reading text | 1280 | 1292 | GPT-6 Astra |
| LMArena Vision: humor | 1287 | Not measured | Only Gemini 3.5 Flash Lite measured |
| LMArena Vision: creative writing | 1260 | 1286 | GPT-6 Astra |
| Neither model has a result on the other 14 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3.5 Flash Lite | GPT-6 Astra | Leader |
|---|---|---|---|
| Neither model has a result on 5 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
Gemini 3.5 Flash Lite costs less
Repository review
50K input + 3K output tokens
Gemini 3.5 Flash Lite costs less
Agent loop
200K input + 10K output tokens
Gemini 3.5 Flash Lite costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | Google Gemini 3.5 Flash Lite | OpenAI GPT-6 Astra |
|---|---|---|
| Maker | OpenAI | |
| Weights | No public weights listed | No public weights listed |
| Released | July 21, 2026 | September 4, 2026 |
| Context window | 1.05M | 1.05M |
| Input $/Mtok | $0.30 | $10.00 |
| Output $/Mtok | $2.50 | $50.00 |
| Coding index | 49.0 | 85.1 |
| Independent measurements behind it | 3 | 5 |
| Cost per solved task | $0.41 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3.5 Flash Lite better than GPT-6 Astra for coding?
Pick GPT-6 Astra for coding: it scores 85.1 on the Vibe Coding Index against 49.0 for Gemini 3.5 Flash Lite. Pick Gemini 3.5 Flash Lite for output tokens 20.0x cheaper ($2.50 vs $50.00 per million) and work measured by CyberBench (Vals AI) or LMArena Text: medicine and healthcare, where it leads.
Which is cheaper, Gemini 3.5 Flash Lite or GPT-6 Astra?
Gemini 3.5 Flash Lite costs $0.30 per million input tokens and $2.50 per million output tokens; GPT-6 Astra costs $10.00 and $50.00. Cost per solved task is known for Gemini 3.5 Flash Lite only.
Which has the bigger context window, Gemini 3.5 Flash Lite or GPT-6 Astra?
GPT-6 Astra, with 1.05M tokens against 1.05M.
How many benchmarks is the Gemini 3.5 Flash Lite vs GPT-6 Astra comparison based on?
74 benchmarks have a result for both models as of October 22, 2026. Gemini 3.5 Flash Lite's coding index rests on 3 independent benchmarks and GPT-6 Astra's on 5. Where only one model has a result, the page says so instead of naming a winner.